Digital marketing became more sophisticated in the 2000s and the 2010s, when[13][14] the proliferation of devices' capable of accessing digital media led to sudden growth.[15] Statistics produced in 2012 and 2013 showed that digital marketing was still growing.[16][17] With the development of social media in the 2000s, such as LinkedIn, Facebook, YouTube and Twitter, consumers became highly dependent on digital electronics in daily lives. Therefore, they expected a seamless user experience across different channels for searching product's information. The change of customer behavior improved the diversification of marketing technology.[18] Display advertising conveys its advertising message visually using text, logos, animations, videos, photographs, or other graphics. Display advertisers frequently target users with particular traits to increase the ads' effect. Online advertisers (typically through their ad servers) often use cookies, which are unique identifiers of specific computers, to decide which ads to serve to a particular consumer. Cookies can track whether a user left a page without buying anything, so the advertiser can later retarget the user with ads from the site the user visited.[25] CPC (Cost Per Click) or PPC (Pay per click) means advertisers pay each time a user clicks on the ad. CPC advertising works well when advertisers want visitors to their sites, but it's a less accurate measurement for advertisers looking to build brand awareness.[63] CPC's market share has grown each year since its introduction, eclipsing CPM to dominate two-thirds of all online advertising compensation methods.[24]:18[62]:1